Methods and systems for injecting information into a power signal, and techniques to capture the injected information are disclosed. Various processes for using the information are also presented, which may relate to the type of device receiving the information. Moreover, techniques for determining the distance of a consumer device are disclosed, as have a specific implementation which relates to mobile consumer devices. Also various ways of encrypting both in-band and out-of-band transmission are disclosed.
|
9. A process for embedding a signature into a power signal using orthogonal frequency division multiplexing comprising the following steps:
a. generating the signature;
b. receiving a power signal having harmonics for transmitting power to a consumer device and for transmitting the signature to the consumer device;
c. demultiplexing the signature into several sub-sequences; and
d. injecting the signature as a mixed signal with the power signal by adding each sub-sequence to a distinct frequency-based sub-channel of the power signal using a modulator;
e. wherein the modulating utilizes orthogonal frequency division multiplexing to embed the information into the carriers near the power signal.
21. A process for tracking a consumer device's power consumption from a power source comprising the steps of:
a. providing a server having a memory for storing an account having a user's payment information and consumer device information;
b. connecting the consumer device to a power outlet to allow power to flow from the power source to the consumer device;
c. sending an in-band transmission to the power source to charge the account associated with the consumer device for the consumption of the power, wherein the step of sending includes generating a signature for identifying the consumer device, demultiplexing the signature into a plurality of subsequences, and modulating the subsequences into the in-band transmission sent to the power source by adding each subsequence to a distinct frequency-based sub-channel;
d. querying the server out-of-band from the power source to determine whether an account associated with the consumer device exists; and
e. sending a response concerning the query to the power source.
1. A process for controlling a consumer device based upon information relating to characteristics of a power source; said process comprising the steps of:
a. receiving a power signal at a power transceiver;
b. embedding a signature of a power source into the power signal using a modulator to form a combined signal, wherein embedding the signature of the power source comprises demultiplexing a signal from a signal generator into multiple subsequences, and wherein the modulator adds each subsequence to a distinct frequency-based sub-channel of the power signal;
c. transmitting the combined power signal in-band to a consumer device;
d. transmitting the signature and additional information out-of-band to a server having records;
e. storing the signature and the additional information in the records;
f. demodulating the combined signal to determine the signature;
g. sending the power from the power source to a power supply coupled to the consumer device;
h. generating a query based on the signature;
i. sending the query out-of-band from the consumer device to the server to request the server lookup information in the records; and
j. responding to the query by sending the additional information to the consumer device.
2. The process of
3. The process of
4. The process of
5. The process of
6. The process of
8. The process of
10. The process of
11. The process of
12. The process of
13. The process of
14. The process of
15. The process of
16. The process of
17. The process of
18. The process of
19. The process of
20. The process of
22. The process of
23. The process of
24. The process of
25. The process of
26. The process of
27. The process of
28. The process of
29. The process of
30. The process of
31. The process of
|
Aspects of the present invention relate to providing an intelligent system for distributing power to consumer devices. More specifically, the invention contemplates sending information concerning sending information in-band and out-of band.
Typical power systems simply distribute power by generating power and allowing the power to flow from a location having a high voltage to an area of low voltage. While power sources may monitor the consumption of energy, they do not generally know any information about the device which consume the energy. Similarly, while the consumer devices can determine whether they are receiving power, they do not generally from what source they are receiving power. Aspects of the present invention overcome this and other problems.
In a first configuration of the present invention, a system is provided for distributing power. The system may contain a power source, a power transceiver, a consumer device, and a server. These four components, may comprise a number of subcomponents to allow the system to provide improved control, regulation, and utility to various connected components. Certain aspects of the present invention may provide a process for controlling a consumer device based upon information relating to characteristics (such as green power) of the power source. Also, various methods of injecting or embedding a signature into a power signal are presented, including generating a baseband carrier wave to distribute power and the information to a consumer device.
To make use of the embedded or encoded information, processes for decoding a signature from a combined power signal are disclosed. To assist in restricting unauthorized access to information relating to the consumer device, processes for encrypting out-of-band communications are disclosed. In addition, a process performed by the power source relating to using information from a consumer device's identifier for security, outages and damaged power lines, or adjusting capacity is disclosed.
Processes for embedding a signature into a power signal using OFDM are also disclosed. Some of these processes may use specific modulation techniques such as PSK to encode the signature into the power signal. Also, various processes for balancing bandwidth considerations and dimensionality concerns are disclosed, as are techniques for adding error code checking. In addition to embedding a signal using OFDM, a process for embedding a signature into a power signal using CDMA is disclosed.
Also various processes for measuring channel length are disclosed, as are processes for tracking a consumer device's power consumption. In addition, a process for determining whether to draw or transmit energy to and from a consumer device is provided.
The process for controlling a consumer device based upon information relating to characteristics of the power source may include sending a power signal to a power transceiver; embedding a signature into the power signal using a modulator to form a combined signal; transmitting the combined power signal to a consumer device; transmitting the signature and additional information to a server having records; storing the signature and the additional information in the records; demodulating the combined signal to determine the signature; sending the power from the power signal to a power supply coupled to the consumer device; generating a query based on the signature; sending the query to the server to request the server to lookup information in the records, by utilizing the signature as a primary key from which to request the additional information; or responding to the query by sending the additional information to the consumer device. The process may also include turning off the power supply if the information from the server indicates the power cost of power exceeds a predefined value; setting the consumer device to run in a power saving mode if the information from the server indicates the power exceeds a predefined value; turning on the power supply if the information from the server indicates the power is less than a predefined value; sending battery characteristics, user charge/discharge preferences, and vehicle-specific information to the consumer device; sending time-of-day restrictions and power cost information; or monitoring the characteristics of the power source to determine how much of the power comes from green sources, and instructing the controller to switch off or move certain electrical devices into a reduced power level if a certain percentage of the power does not come from green sources.
The process for embedding a signature into a power signal using OFDM may include: generating the signature; receiving a power signal having harmonics for transmitting power to a consumer device and for transmitting the signature to the consumer device; demultiplexing the signature into several sub-sequences; modulating the sub-sequences onto one or more carriers near the power signal using a modulator; wherein the step of modulating utilizes OFDM to embed the information into the carriers near the power signal. The power signal may comprise locations of peak and nonpeak spectral magnitude, and the step of modulating may add the sub-sequences to the carriers in the location of nonpeak magnitude. Additionally, the modulator may be instructed to use instantaneous phase or amplitude discontinuities to produce sub-channel modulation and improve carrier error rate in the power channel; the step of modulating uses minimum shift keying (MSK), binary PSK (BPSK), quadrature-carrier PSK (QPSK), or differential PSK (D-PSK) to produce the sub-channel modulation; the step of modulating may use frequency modulation to produce the sub-channel modulation; the step of modulating may use Amplitude Shift Keying (ASK) to produce the sub-channel modulation. In some embodiments, the embedded information may have a spectral containment of at least 90%; the embedded information may be embedded at a bandwidth of 5 Hz, 10 Hz, or 20 Hz; the embedded information can transfer information at 0.5 bits/Hz and 2.5 bits per second if the modulator is instructed to use binary phase shift keying at a bandwidth of 5 Hz; the embedded information can transfer information at 1.0 bits/Hz and 20 bits per second if the modulator is instructed to use quadrature carrier phase shift keying at a bandwidth of 20 Hz; the modulator may place the sub-channels near the 12th, 14th, and 16th harmonics of the power signal; the modulator may utilize forward error correction coding to provide the signature with error protection; the error correction coding may be coded OFDM; the error correction coding may employ a convolutional code; the error correction coding may employ a concatenated Reed-Solomon code and time/frequency interleaving; or the error correction coding may be turbo coding or low-density parity-checking.
The process for tracking a consumer device's power consumption from a power source may include the steps of: providing a server having a memory for storing an account having a user's payment information and consumer device information; connecting the consumer device to a power outlet to allow power to flow from the power source to the consumer device; sending an in-band transmission to the power source to charge the account associated with the consumer device for the consumption of the power; wherein the step of sending includes: generating a signature for identifying the consumer device: wherein the signature comprises a code, and the code is stored on a VIM; demultiplexing the signature into a plurality of subsequences; and modulating the subsequences into the in-band transmission. Additionally, the steps of demodulating the in-band transmission to determine the signature at the power source; querying the server to determine whether an account associated with the consumer device exists; sending a response concerning the query to the power source may performed. If the response indicates an account associated with the consumer device is present: the steps of monitoring the flow of the power from the power source to the consumer device; detecting when the consumer device ceases drawing power; sending a total amount of energy consumed to the server; determining how much to charge the account for the energy consumed; transmitting the total charge for the energy and a total amount energy which was consumed by the consumer device; or displaying the total charge and energy consumed with a component of the consumer device may be performed. If the response does not indicate an account associated with the consumer device is present, the step of transmitting a message to the consumer device to cause the consumer device to display information to indicate that the consumer device is not associated with an account may be performed. Additionally, the step of transmitting a price for the energy to the consumer device once the identity of the consumer device has been determined; wherein the consumer device is a vehicle or more specifically an electric or hybrid automobile may be performed.
Embodiments of the present invention may include a consumer device having a controller and a power supply having a charge. The controller may comprise instructions stored on computer readable memory to cause the consumer device to execute the steps of: establishing a maximum cost per watt of energy, and a minimum cost per watt of energy; drawing power from a power source if the cost of the power is less than the maximum cost per watt, and the charge on the power supply is less than a predefined percentage; sending power to the power source if the power source is offering more than the minimum cost per watt, and the charge on the power supply is greater than a predefined percentage; wherein the consumer device is an electric or hybrid automobile.
Aspects of the present invention provide a system 10 for intelligent power distribution.
Power source 100 may be a large power generation facility such as the Hoover Dam, a local power facility such LILCO, PECO, or ConEdison, or a power generator such as the power generators made by Honeywell, Briggs and Stratton, or Generac. The power source 100 may also comprise a power generator 110 for generating a power signal 710 (
Power transceiver 200 may be used to add a signature (650,
The consumer device is a device which draws electricity into its power supply 310 (such as a washing machine, lamp, or air conditioner) in order to perform some function. The system 10 may also comprise a generator or battery. In such a system, power may flow from the generator back to power source 100. Additionally, the system 10 may also may be a hybrid vehicle and power may flow from the battery of the hybrid device to the power source 100, and from the power source 100 to the battery of the hybrid device. The controller 320 of the consumer device 300 may comprise a memory with instructions in the memory for causing the consumer device to execute a number of different functions (which are explained In the embodiment shown in the
The server 500 may have a processor, memory, and software for accessing, analyzing, and delivering information to the other components of the system 10. For example, the processor 560 may control input 510, information input 540, and output 530 which transmit information to and from the server. The processor 570 may execute software routines stored in the memory 550 which allow the processor 570 to look up information in the records 520 of the server 500.
In a first configuration of the invention, the power source 100 may use a power generator 110 to generate (S1) a power signal which may be transmitted (S2) to the power transceiver 200 through the output 120. The power transceiver 200 may receive (S3) the power signal using the power signal receiver 210, embed or inject (S4C) information in the power signal using the modulator 220, and transmit the combined power signal (S5) to the consumer device 300 using the output 230. The output 230 may also send (S15) information, such as signature, origin of the power, how the power was generated (coal, oil, wind, etc), cost of the power, etc) to the information input 540 of the server 500. The server 500 may store the information and the signature in its records 520. In some embodiments, the server 500 may store (S17) the information in a database, wherein the signature serves as a primary key from which a query can be generated to obtain the additional information about the signature. Returning to step (S5), the consumer device 300 may comprise a consumer transceiver 400 which can process information embedded in the power signal, and receive (S6) the power signal from power transceiver 200 with an input 410. The input 410 may transmit the power signal into a demodulator 430 which determines (S7) the signature, and optionally using a splitter 420, send (S8) the power signal to the power supply 310 of the consumer device 300, and send (S9) the signature to the output 450 which may send (S11) the signature to the input 510 of the server 500. The output 450 may also send a query to the server 500 to request the server to lookup (S12) information in the server's records 520 about the signature, and return (S13) information about the signature back to the consumer device 300. The server 500 may use an output 530 to transmit (S13) information to a server input 460 of the consumer device 300. The server input 460 may capture the information from the server 500, and send (S14) the information to the consumer device controller 320. The device controller 320 may perform (S18) a variety of functions depending on the information received. For example, the controller 320 may turn off (S19) the power supply if the information from the server indicates the costs for the power is greater than 10 cents per kilowatt. Similarly, the consumer device 300 may autonomously perform (S18) a variety of functions depending on the information received (S7) and demodulated (S8, S9), if the consumer device 300 is suitably configured. For example, the signature transmission (S5) may include information about the instantaneous price of electricity, or about current conditions on the local power grid. If the controller 320 and software 495 of the consumer device 300 have been pre-configured to decode and respond to these items of information (S8, S9), then the consumer device 300 may perform one or many such functions in accordance with the pre-configured instructions. Such actions may include completely disconnecting the consumer device 300 from the power grid, setting the consumer device to run in a power saving mode if the information from the server indicates the power exceeds a predefined value; causing the consumer device 300 to accept additional power from the grid through input 410, or causing the consumer device 300 to provide power to the grid through input 410 from its local power reservoir.
The information sent by the server 500 may depend on the type of the consumer device 300 connected to the transceiver 400. For example, if the device is a hybrid motor vehicle this information may include battery characteristics, user charge/discharge preferences, or other subscriber-specific, vehicle-specific, or network-specific information which is important for the present transaction. The server 500 may send this information to consumer device to allow the consumer device to check or reconcile that the information in the server 500 which relates to the characteristics of the consumer device 300 are correct. In some configurations, the consumer device 300 will return it's own copy of this information to the server 500 to allow the server 500 to update its records 520. If the device 300 is a washing machine or an air conditioner or another type of device which presents a load to the power network, this information may include time-of-day restrictions, electricity cost information, or other subscriber-specific or network-specific information which is important for the present transaction. If the device is an electric generator or wind turbine or solar panel which can create energy to be released into the electric power network, this information may include time-of-day restrictions, electricity cost or pricing information, or other subscriber-specific or network-specific information which is important for the present transaction. Moreover, the consumer device 300 may use the information to change the way the consumer device 300 functions based on the received information. For example, if the information sent to the consumer device 300 indicates that the cost of the electricity is greater than a predetermined value, the controller 320 may instruct the device 300 to enter into a power saving mode. In another example, a company (which represents the load on the system 10) may wish to publicize its commitment to green or renewable energy sources (which may be more expensive.) In such a case, the company may monitor the source of the power to determine how much of its power comes from green sources. Controller 320 may be programmed to switch off or move certain electrical devices into a reduced power level if a certain percentage of its power does not come from green sources. The company may also use this information to validate or enforce a service contract with the power source which requires a certain instantaneous or average percentage of power from green sources.
One of functions of the power transceiver 200 may be to embed or inject a signature 650 into the power signal 710. A signature 650 is an identifiable aspect of a power signal 710, and may be expressed in a digital or analog form. It may be a randomly generated number (based on a seed value or an aspect of the power signal) or specifically generated via an enumeration algorithm. Once this “digital” signature is created or known, it can be modulated to create an analog signature waveform which is then added to the power signal. In some configurations, the digital signature may be comprised of several measured quantities from several different observable and related signals which, when considered together, may represent the complete signature. The signature may be visualized as a set of discrete quantities and/or analog signals that, when considered together, represent an analog or a digital signal which identify the generator of the power waveform. For example,
In an alternate configuration of the present invention, the processor 240 could convert the combined signature waveform from analog form to digital form using converter 270, and store the digital form as the signature.
Referring back to
To send an out-of-band communication to a server 500, the consumer device 300 may send the digital or analog signature to the server 500. The consumer device 300 may also send an identifier to the server 500 or another consumer device via out-of-band transmission, or to another consumer device or power transceiver 200 via an in-band transmission. An identifier may be a number or other code used to identify the consumer device 300. This identifier may also be the discrete signature of the consumer device 300, suitably modulated for transmission on the channel currently in use. This identifier may also contain or be associated with additional digital information which is modulated and transmitted in the same fashion.
Encryption may be used to secure the out-of-band communications between the power transceiver 200 and the consumer transceiver and server 500. For example, the server 500 may receive this communication, look-up additional information about the signature in the server's records 520, encrypt the information, and send the encrypted information to the consumer device 300. The server 500 may also send a public key to the consumer device 300. Using the public key, the consumer device 300 may encrypt data before sending it to the server 500. In this embodiment, the private key corresponding to the previous public key would be known only to the server 500, and the server 500 would use this private key to decrypt data which had been encrypted by the consumer device 300 using the public key.
Alternate encryption techniques may be used to secure the transmissions. For example, the consumer device 300 may comprise a public key and a private key in its memory 490. The microprocessor 480 may send the public key to the server 500. The microprocessor 570 of the server 500 can use the public key to encrypt the information before it sends the information to the consumer transceiver 400. The consumer transceiver 400 can receive the encrypted information from the server 500 using server input 460. The microprocessor 480 of the consumer transceiver 400 can use the private key to decrypt the encrypted information and then send (S14) the information to the controller 320. Though these embodiments describe using public, private key encryption techniques, in other configurations, the server 500 could use a different encryption system or not use encryption at all. Moreover, information exchange between the power transceiver 200 and the consumer device 300 may be encrypted as may the exchange of information between the power transceiver 200 and the server 500. Additionally, the public/private key exchange and the resulting encrypted message interchanges may occur using either an out-of-band transmission or an in-band transmission.
Power companies may also use this technology to track and measure the usage of power by the consumer devices. When a consumer device 300 receives power it may send a signal in-band, upstream for indicating its identity to the power source or other monitoring entity so that the power source 100 can track the consumer device's 300 energy consumption, location, physical connection, signal propagation path, or other parameters pertaining to electric power consumption and generation. A consumer device's identifier may be stored in memory 490 and/or generated via the processor 480. Should the flow of information back to the power source be interrupted, the interruption may indicate a problem with the consumer device 300, the power signal, or the power lines. Software 150 containing instructions in the memory 140 of the power source 100 may cause the power source 100 to monitor for changes in the consumption of electricity. For example, should a cluster of consumer devices all fail to return their signature at a similar time, the processor 130 of the power source 100 may determine there is a problem with the power generator 110 or with the power lines. By analyzing the location of the consumer devices 300 which have power (i.e. are able to respond with signature transmissions) and those that do not have power (are unable to respond with signature transmissions), the location of the damaged power line can be determined. Moreover, the power source 100 or a collection of several power sources 100 may be able to reroute power to the consumer devices 300 once the processor 130 has determined which lines are malfunctioning. Another embodiment of the present invention, may involve providing instructions in the memory 140 of the power source to monitor fluctuations in a consumer device's or location's usage. A change in the pattern of usage may indicate a potential problem with the consumer device or unauthorized usage. For example, if the consumer device were a computer, and the computer is only powered on between 9-5 PM, and it is turned powered on at 2:00 AM, the power transceiver or other monitoring entity may determine security at the location of the computer may have been compromised. Similarly, by monitoring and/or recording the locations that electric vehicles typically attach to the grid for charging, the power company may adjust its infrastructure to provide additional capacity, or allow for dynamic system reconfiguration to compensate for potential oversubscription situations due to these large, mobile consumer/generator devices. An application of this process would include a database controlled by the power company which keeps track of the physical connection of multiple electric vehicles. This database would logically be contained or implemented in the records 520 and software 560 of server 500. With these records 520 and the in-band, bidirectional transmissions 450 and 460, the server 500 would know, at any point in time, which specific feeders and/or distribution links have (or had) electric vehicles physically attached. Using the technologies described herein, the server 500 and associated software 560 would save in records 520 time-based information about the electric vehicles, the battery in the vehicles, the owner preferences/requirements for charge, and other important parameters related to the grid configuration, power supply and usage, and overall stability of end-to-end electric service being provided or consumed by devices on the grid. The items of information stored in records 520 which pertain to interactions between power sources 100 and consumer devices 300 and which may be used to affect or improve grid stability or efficiency could then be leveraged by software 560 to effect in-band or out-of-band communication to a multiplicity of consumer devices 300 and remotely control or optimize end-to-end grid performance.
There are several ways the power transceiver can modulate and inject or embed the signature into the power signal 710. A first way, involves using OFDM injection (orthogonal frequency division multiplexing) which uses several non-overlapping narrow-band channels (“frequency division”) to carry several streams of digital data in a parallel fashion 730.
In one or more sub-channels, the modulator may be instructed to use instantaneous phase discontinuities such as single-carrier phase shift keying (N-PSK), or quadrature-carrier PSK (QPSK), or differential PSK (D-PSK), or a version of minimum-shift keying (MSK) to produce sub-channel modulation or to provide an improved error rate in the power channel without requiring carrier recovery for coherent demodulation. Examples of characteristics of several PSK-based sub-carrier modulation approaches used in embodiments of the present invention are shown in Table 1 below. The table shows the effective bit-rate for a given modulation scheme based on a specific sub-channel bandwidth, for the two cases of 90% and 99% spectral containment. For the use of OFDM in embodiments of the present invention, the bit-rates in the table indicate an approximate throughput per sub-carrier of the signature data plus any bits required for forward error-control coding.
TABLE 1
Modulation
20 Hz BW
10 Hz BW
Scheme
90%
99%
90%
99%
MSK
20 bps
16 bps
10 bps
8 bps
BPSK
10 bps
<1 bps
5 bps
<0.5 bps
QPSK
20 bps
2.5 bps
10 bps
~1 bps
Table 1 shows spectral containment for three modulation schemes (MSK, BPSK, and QPSK). When a modulator converts discrete data (individual bits or groups of bits) into a continuous waveform (such as an analog signal) the resulting waveform is modified in various ways. The modifications may include, for example, an abrupt change in the waveform to represent the beginning and end of each piece of discrete data. For example, if the modulation scheme is “PSK” (Phase Shift Keying), then the modulator abruptly changes the phase of the analog signal to indicate a bit or symbol transition. The phase of an analog signal generally refers to a shift in the positive or negative x direction of a wave. In modulation for the purpose of communication, the waves (carriers) are sinusoidal functions of time. So, the x direction of the carrier is generally considered to be the time axis, and a phase shift refers to a delay or advancement (in time) of the natural evolution of the sinusoidal carrier. For example, sin(t±180°)=−sin(t). Phase modulation is a process similar to frequency modulation, wherein the phase of a carrier wave is modified to embed the desired information. Similarly, if the modulation technique is ASK (Amplitude Shift Keying), the amplitude of the wave is changed to indicate a bit or symbol transition.
The modulated waveform generated by power generator 110, power transceiver 200, or consumer device 300 may have modulation artifacts, which may be abrupt changes in the waveform, a warping of the waveform's shape, or a spurious, localized energy burst in the frequency spectrum. Certain techniques may be employed to improve the spectral containment of these modulation artifacts. Spectral containment refers to the percentage of the modulation artifacts which, when injected alongside the original power signal, do not bleed into one another or otherwise adversely affect the power signal. Some modulation schemes minimize these artifacts, and so have better spectral containment for a given bit-rate or carrier frequency. In some embodiments, the modulator 220 may generate a modulated signal with a higher spectral containment, thereby possibly reducing the effective bits per second of the transmission.
The modulator 220 of the present invention may use MSK (Minimum Shift Keying), BPSK (Binary Phase Shift Keying), or QPSK (Quaternary Phase Shift Keying) to reach a balance between spectral containment and bandwidth of the transmission. As shown Table 1, in a 10 Hz or 20 Hz section of spectrum, maintaining 99% spectral containment (i.e. relatively no leakage), more bits-per-second can be transmitted with MSK than with BPSK or QPSK. If minimizing leakage is less important and 90% containment is sufficient, QPSK and MSK have about the same throughput. Thus, if the modulator 240 uses the MSK algorithm to modulate the signature bits onto a sinusoidal carrier (thereby producing a modulated signature waveform), the spectrum of the resulting signature waveform will be much narrower than if the modulator used BPSK or QPSK to modulate those same signature bits onto the sinusoidal carrier. Similarly, after injection or embedding of the modulated signature waveform into (onto) the original power signal, the “disturbances” created by the presence of the modulated signature waveform might be more predictable or controllable than with modulation algorithms with poorer spectral containment.
As shown in Table 1 and Table 2, lowering the BW (bandwidth) generally decreases the amount of data that can be transmitted in a given amount of time. Table 2 shows the approximate number of bits per second that can be transmitted by several different PSK algorithms in various channel bandwidths (5 Hz, 10 Hz, 20 Hz). The various PSK algorithms in Table 2 use different numbers of possible phase shifts (M) to represent symbol or bit transitions. For example, when M=2 (BPSK) there are two possible phase-states that the carrier waveform can inhabit. A “1” data bit corresponds to a particular phase-state, and a “0” data bit corresponds to the other phase-state. In contrast, when M=8 (8PSK) there are 8 possible phase-states that the carrier waveform(s) can inhabit. Each distinct group of 3 consecutive data bits (“000”, “001”, “010”, etc.) determines which phase-state the carrier waveform inhabits.
Bandwidth is related directly to maximum data throughput because to transmit a number of discrete information bits through a channel using a carrier signal, the modulator 220 has to make modifications to the carrier signal. There are only so many changes that can be made to a carrier signal per unit of time, so the power transceiver 200 can send more information per second by using a wider channel bandwidth, and a higher-frequency carrier. Increasing spectral containment decreases the amount of data that can be transmitted, because the process of increasing spectral containment involves compacting the spectrum of the modulated signal in order to prevent or reduce bleeding onto an adjacent spectrum. Compacting the spectrum is equivalent to requiring a lower channel bandwidth, which reduces the number of physical changes per unit time, which reduces the number of bits that can be used for modulation, which reduces bit rate.
Testing of various PSK modulation techniques have revealed that as frequency and the dimensionality (i.e. the Phase Shift M-property) increase, more data per second can be transmitted, as shown in Table 2.
TABLE 2
BPS for a given channel
M-ary
BW
PSK
5 Hz
10 Hz
20 Hz
M
bps/Hz
BPSK
2.5
5
10
2
0.5
QPSK
5
10
20
4
1
8PSK
7.5
15
30
8
1.5
16PSK
10
20
40
16
2
Thus if the modulator 220 is instructed to use binary shift keying at a bandwidth of 5 Hz, 2.5 bits per second can be transferred at a rate of 0.5 bits per Hz. Similarly, if the modulator 220 is instructed to use quadrature carrier phase shift keying a bandwidth of 20 Hz, 20 bits per second can be transferred at a rate of 1 bits per Hz.
Theoretically, if the software 260 of the power transceiver were programmed to send more data bits per change in the carrier waveform, the throughput or bandwidth of the transmission would increase (bits/Hz). However, as M increases the complexity of the algorithm the power transceiver would use would increase, and the possibility the consumer transceiver will make errors in decoding the bits increases. For example, BPSK is very robust to bit errors and the consumer transceiver 300 is less likely to make errors in decoding the transmission, but with 16-PSK a consumer transceiver 300 is more likely to make errors, making 16 PSK less desirable.
When implementing the disclosed system several different parameters may need to be customized or adjusted to compensate for local characteristics of the power signal and physical channel. These parameters may include the number and width of various sub-channels, the power level of the transmissions in each sub-channel, and the requirement for various error-correction schemas in each sub-channel or across the collection of sub-channels. For example, current research has indicated that transmitting the signature on or near the 12th, 14th, and 16th harmonics utilizing QPSK modulation has provided adequate data throughput (bits/second), low error rate, simple implementation, low distortion of the fundamental, and good spectral containment.
Additionally, in some embodiments it may be helpful to implement a forward error correction coding technique such as Coded OFDM (COFDM). In these embodiments, the modulator 220 may implement Coded OFDM is OFDM with an error-correcting code applied to the data-bits before modulation. The error-correcting code essentially scrambles the original data in a controlled fashion and inserts extra data for purposes of redundancy. This process improves the robustness of the transmission, and provides the consumer transceiver 300 additional techniques for correcting errors after demodulating the signature from the combined signal 720 (
The modulator 220 may modulate the binary signature data using OFDM techniques with one or several sub-channels, or using conventional modulation techniques with one or several sub-channels. In each case, the specific modulation techniques used in each sub-channel may be a combination of techniques as described herein to create a combined power-plus-signature signal.
Code-Division Multiple Access (CDMA) may also be used in embodiments of the present invention for coding & modulating the in-band signature. CDMA, also known as “Direct Sequence Spread Spectrum” (DSSS), uses a pseudo-random binary sequence called a Pseudo-Noise code (PN code) or “chip sequence” to discretely modulate the payload data sequence. In this discrete modulation, the data sequence is multiplied by the chip sequence. The PN code has a much shorter bit-period than the bit-period of the data sequence, so the spectrum of the resulting signal is “spread” over a larger frequency range. The “coding gain” of the CDMA process is the ratio of “chip bits” or PN code bits per “data bit”. The bandwidth of the resulting “spread spectrum” signal is computed from the effective bandwidth of the original payload signal multiplied by the coding gain.
Binary-PSK (BPSK) may be used as a channel modulation technique for data streams that result from DSSS techniques. An important characteristic of CDMA is the orthogonality of the PN codes that are used to modulate and spread the payload data sequences. The orthogonality of these PN codes allows multiple payload sequences (each with different PN code) to have simultaneous use of a common spectrum (“multiple access”) while preserving unique detection (“code division”).
The modulator 220 may modulate binary signature data using a PN code with a prescribed spreading gain, such as 16 chips/bit. The modulator may then modulate the resulting digitally spread signal using BPSK with a prescribed carrier frequency (say, 750 Hz) to create a combined power-plus-signature signal. The modulator 220 may need to optimize certain parameters of the modulation process which may include the number and width of various sub-channels, the spreading gain and type of modulation in each sub-channel, the PN codes for spreading, the number of data bits transmitted in each sub-channel, the power level of the signature transmissions, and the requirement for various error-correction schemes in each sub-channel or across multiple sub-channels.
Unique sequences such as PN codes may also be used to determine range or distance of the consumer device 300 from the power transceiver 200 or power supply 100. When a unique PN sequence is injected into a channel at the power transceiver 200, the consumer device 300 may reflect the signal back to the consumer device 300. The unique properties of the PN sequence can be used to estimate channel length via a correlation algorithm. This correlation algorithm can detect time-shifts in similar sequences, and then relate these time-shifts to physical distance.
The system may be configured to measure channel length for diagnostic purposes to optimize or categorize cable deployments, locate singularities, or unique, damaged, or problematic sections of the power line carrying the power signal. To determine channel length, the following processes may be used. It should be noted that some of the steps are optional and many steps can be performed in a differing sequence than the order provided. The following instructions may be stored in the memory of the consumer transceiver and/or the power transceiver. The instructions may take the form of computer executable code that the microprocessor of the respective transceiver can execute. With reference to
The software 260 in the memory 250 of the processor 240 may instruct the processor 240 to multiply the first transmitted bit by the first return bit, multiply the second transmitted bit by the second return bit, and so on. Then the processor would sum all the product bits, and determine the sum is 5, in this example. If the processor shifts the received transmission one unit of time to left, the sum of the bits of the received code yields a sum of 4. If the processor shifts the received unit again to the left, the calculated sum is 3. If the processor shifts the received unit twice more to the left, we have the example shown in
One recognized difficulty with electric or hybrid vehicles (such as cars, motorcycles, boats, RVs, and airplanes) relates to the difficulty with establishing charging stations to recharge their batteries. Prior art solutions have involved preauthorizing the flow of power from an outlet to charge the vehicle. In such a solution, a user would drive up the charging station, insert a credit card, the charging station would authorize the payment, and turn the outlet “on” for a certain amount of time, allowing the vehicle to draw a certain amount of energy. This technique requires expensive equipment, possible credit card machines, and modification to existing electrical infrastructure. This cost would be a large deterrent for public parking lots, hotels, and other areas where cars are parked. It also would not work at a “neighbor's” house for example, as the neighbor would not likely have the infrastructure necessary to charge for the energy. What is needed is some sort of automated billing system, wherein the person charging his or her vehicle is automatically charged for energy he or she consumes when the vehicle is being charged. Ideally, no configuration would be needed so that a second user could maneuver his or her vehicle to the outlet and also benefit from a simple charging system. Aspects of the present invention provide such a solution.
With reference
In one configuration of the invention, a user may have the option to create an account 580 in the memory 550 of the server 500. The account 580 may include a billing address, credit card information, information about the consumer device 300′, power draw information, and power transmission information. When the user connects his or her device 300′ to the outlet, power flows (T1) to the input 410 of the consumer device 300 from the power source 100′. The input 410 of the device may send the information to the processor 480 of the consumer device 300 may inform the power transceiver 200 that the user's account should be charged for the energy the device 300 will consume. To arrange this, the consumer device 300 will use it's demultiplexor 422 (T4) and modulator 423 (T5) (as described above in [0023]) to add a signature (possibly from the VIM T3) to the power signal. Output 415 will return (T6) the energy to the input power transceiver. In some cases, the electric infrastructure may comprise additional transceivers or listener devices at certain places in the power network in order to retrieve the signature transmissions from the in-band channel(s) and forward them to the power source or to the server. Also, the listener devices may track other things related to power consumption, including specific location (on the wire), time-of-day, and other tendencies. The input 215 may send (T7) the power signal to the processor 240 and demodulator 290, the power transceiver 200 may determine (T8) the identity of the vehicle 300′ by discerning the signature from the received power signal. The power transceiver 200 may then query (T9) the server 500 to determine if the vehicle 300′ has an account 580. Using its output 530, the server 500 may transmit (T10) a response to the query to the power transceiver 200. If a positive answer is transmitted, the power transceiver 200 may monitor (T11) the usage of the outlet (using the processor 240 and the input 215), and when the user disengages the use of the outlet, the consumer device 300′ will no longer be able to transmit its identity. The power transceiver 200 may note the lack of the identity data being transmitted to the power transceiver 200 and may send (T12) the total amount of energy consumed to the server 500, which (using a dollars/watt factor for example) may determine how much to charge the user for the energy. The server 500 may then charge (T13) the user's credit card or otherwise debit the user's account. The server 500 may also transmit (T14) the total cost of the energy (and perhaps how much energy was used) to the server input 460 of the consumer device 300′. The server input may send (T14) this information to the controller 320 which may instruct (T16) the display 330 to display (T17) this information on a LCD screen 330, for example. If the user does not have an account 580 associated with the signature, the server may transmit (T14) a message to the user through the consumer device 300′to cause the controller to instruct (T16) the display to inform (T17) the user that no account 580 has been established. Also, in some embodiments, the server 500 will transmit (T14) the price of the energy to the consumer device 300′ once the identity of the consumer device 300 has been determined. It should be appreciated that the above method, while particularly useful for mobile devices like vehicles, could be used by any consumer device having an identifier, wherein the user wants the power company to charge his account for the device's use of the electricity.
Alternatively, rather than charging the user's device for electricity drawn, if the device is one which has a battery or power saving device, the device could send power back to the power source or direct power to a third locations (such as one of the power source's other customers). This feature might be desirable for a power company in periods of high power consumption, or when a damaged power line is prevented from distributing power to a particular location. For example, if the distribution channels to a first location are damaged, the power transceiver 200 could request power from the battery of a hybrid car to send power to the first location. In such a configuration, it is contemplated that the power transceiver 200 may credit the account associated with the battery which is being depleted of energy. More specifically, settings in the account may be configured so that the consumer device 300′ will draw power from the power source 100 if the power costs less than A cents/watt and the charge on the battery is less B percent (energy draw settings), and will transmit if the power source 100 will pay more than C cents/watt for the energy and the charge on the battery is greater than D percent. (energy transmission settings).
In conclusion, the above disclosure has provided ways of injecting information in a power signal, and techniques to capture the injected information. Various processes for using the information have been disclosed, which may relate to the type of device receiving the information. Moreover, techniques for determining the distance of a consumer device 300′ have been disclosed, as have a specific implementation which relates to mobile consumer devices 300′. Also various ways of encrypting both in-band and out-of-band transmission have been disclosed. Although specific implementations have been set forth above, they are intended to be exemplarily only, and the scope of the invention should be limited only by the meets and bounds of the following claims.
Loporto, John J., McClellan, Stan
Patent | Priority | Assignee | Title |
10020677, | Oct 30 2014 | TRC COMPANIES, INC | System, method, and apparatus for grid location |
10079765, | Oct 30 2014 | TRC COMPANIES, INC | System and methods for assigning slots and resolving slot conflicts in an electrical distribution grid |
10356055, | Jun 09 2011 | TRC COMPANIES, INC | System and method for grid based cyber security |
10459411, | Apr 15 2011 | TRC COMPANIES, INC | System and method for single and multizonal optimization of utility services delivery and utilization |
10498394, | Feb 19 2013 | Lockheed Martin Corporation | Methods for discovering, partitioning, organizing, and administering communication devices in a transformer area network |
10541724, | Feb 19 2013 | TRC COMPANIES, INC | Methods for discovering, partitioning, organizing, and administering communication devices in a transformer area network |
10554257, | Feb 19 2013 | TRC COMPANIES, INC | System and method for inferring schematic and topological properties of an electrical distribution grid |
10564196, | Jun 13 2013 | TRC COMPANIES, INC | System and method for detecting and localizing non-technical losses in an electrical power distribution grid |
10770917, | Nov 08 2016 | PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO , LTD | Power transmission system transmitting powers from multiple power transmitter apparatuses to multiple power receiver apparatuses, and capable of distinguishing and separating transmitted powers |
9013902, | Sep 10 2009 | The University of Tokyo | Multi-terminal power conversion device, multi-terminal power transfer device, and power network system |
9024571, | Sep 28 2012 | Honda Motor Co., Ltd. | Charging of electric vehicles based on historical clean energy profiles |
9602475, | Jun 09 2011 | Astrolink International LLC; Dominion Energy Technologies, Inc. | System and method for grid based cyber security |
9647994, | Jun 09 2011 | TRC COMPANIES, INC | System and method for grid based cyber security |
9848446, | Aug 03 2011 | TRC COMPANIES, INC | System and methods for synchronizing edge devices on channels without carrier sense |
9853498, | Oct 30 2014 | TRC COMPANIES, INC | System, method, and apparatus for grid location |
9923825, | Oct 30 2014 | Astrolink International LLC; DOMINION ENERGY TECHNOLOGIES, INC | System and methods for assigning slots and resolving slot conflicts in an electrical distribution grid |
Patent | Priority | Assignee | Title |
20040110044, | |||
20040227621, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Jun 08 2009 | Power Tagging Technologies, Inc. | (assignment on the face of the patent) | / | |||
Jul 30 2009 | LOPORTO, JOHN J | POWER TAGGING TECHNOLOGIES, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 023055 | /0318 | |
Jul 30 2009 | MCCLELLAN, STAN | POWER TAGGING TECHNOLOGIES, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 023055 | /0318 | |
Mar 28 2011 | POWER TAGGING TECHNOLOGIES, INC | DOMINION ENERGY TECHNOLOGIES, INC | SECURITY AGREEMENT | 026067 | /0198 | |
Mar 28 2011 | POWER TAGGING TECHNOLOGIES, INC | Astrolink International LLC | SECURITY AGREEMENT | 026067 | /0198 | |
Mar 12 2014 | POWER TAGGING TECHNOLOGIES, INC | Astrolink International LLC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 051047 | /0478 | |
Mar 12 2014 | POWER TAGGING TECHNOLOGIES, INC | DOMINION ENERGY TECHNOLOGIES, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 051047 | /0478 | |
Jun 19 2019 | Astrolink International LLC | Lockheed Martin Corporation | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 051241 | /0270 | |
Nov 18 2019 | Lockheed Martin Corporation | TRC COMPANIES, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 052469 | /0136 |
Date | Maintenance Fee Events |
Feb 27 2017 | M1551: Payment of Maintenance Fee, 4th Year, Large Entity. |
Apr 19 2021 | REM: Maintenance Fee Reminder Mailed. |
Oct 04 2021 | EXP: Patent Expired for Failure to Pay Maintenance Fees. |
Date | Maintenance Schedule |
Aug 27 2016 | 4 years fee payment window open |
Feb 27 2017 | 6 months grace period start (w surcharge) |
Aug 27 2017 | patent expiry (for year 4) |
Aug 27 2019 | 2 years to revive unintentionally abandoned end. (for year 4) |
Aug 27 2020 | 8 years fee payment window open |
Feb 27 2021 | 6 months grace period start (w surcharge) |
Aug 27 2021 | patent expiry (for year 8) |
Aug 27 2023 | 2 years to revive unintentionally abandoned end. (for year 8) |
Aug 27 2024 | 12 years fee payment window open |
Feb 27 2025 | 6 months grace period start (w surcharge) |
Aug 27 2025 | patent expiry (for year 12) |
Aug 27 2027 | 2 years to revive unintentionally abandoned end. (for year 12) |